Casting runner



T. BRINKMANN CASTING RUNNER Dec. 6, 1932.

Filed June 20. 1929 Patented Dec. 6, 1932 PATENTIOFFIICE THE-ODOR 33m, 01 HASPE, GERMANY caa'rlim Baum Application filed June 20, 1929, Serial No. 872,492, and in Germany March '8, 1929.-

also after temporary missing or nonlling' of a mould due for example to theclogging of the vent hole'or to too rapid cooling of the steel, when casting ingots of different sizes on one casting bed, through carelessness-ion the part of the caster, crooked axial direction or unfavourable position ofa vent hole, etc.

If attempts arefmade to prevent splashing and skin formation by careful ouring, ingots often stop N (do not rise) cause the metal has become too cold.

sections-specially when workin heavy steel charges-that the metal flowing romthe vent hole and distributing over the comparative ly cold casting bed'has already solidified on reachin the mould wall and is flown over by 39 the in owing metal. With silicated and aluminized steels, a considerable portion of the ingots become, at slow pourlng, often cracked and is rendered useless through the so-called flowing over of the steel.

If' the vent hole is not absolutely vertical the ct diverted to one side by this inclination was es against the mould wall and causes eating in owing'to local overheating whereby the moulds become useless.

40 Qwing to this lateral deviation of the jet from the vertical the solidification of the inflowing metal is not uniform, 'sothatthe finished material behaves irregularl "under stress owing to the irregularity in-t e structure; i I

It has already been proposed, to obviate these inconveniences by throttling the cast-.

ing metal inthe vent hole. With this'object in view a slot shaped form of the Vent hole was used, care being taken, that this vent hole -channel of thechannel stone; as this pro- It often happens with. larger ingot cross cular vent holes. This object is best fulfilled was not greater than the hitherto used circular vent holes, and'as far as possible smaller in its horizontal cross section than the vertical cross section of the horizontal supply posal started from the intention to make the flow of the casting metal to the interior of .the ingot mold as slow as possible, in order to prevent casting metal from being moved alon'g'which, for instance by whirling occuring in the mold, had been submitted to loss of heat on the mold walls or on the mold bottom formed by the casting bed, these portions of casting metal solidifying then in the hotter casting metal under. other conditions than this latter. This proposal even demanded slow flowing of the casting metal into the mold so that this metal solidified immediatelyat the point at which it came first into contact with the bottom of the mold or with the walls of the mold.

This proposal has, not to mention that it has to be condemned also for other reasons, the fundamental defect, that it directly causes, by the required narrow and short slots, the danger of clogging of the vent hole and thereby the feared failing of ingot formation.

The invention is based on the knowledge, confirmed by exhaustive experiments, that the hitherto used casting measurements and also the above proposal are wrong, if the above mentioned inconveniences have to be avoided,

and that just the o posite of that has to be done, which has een hitherto proposed.

According to the invention vent holes of the greatest-possible cross section-are to be used for casting ingot blocks, slab blooms and similar blocks, and not the well known, comparatively narrow circular vent hole through which a foundation like jet of the casting metal squirts out at high speed under high pressure, nor short slots of at the utmost the cross section size of commonly used cirby slots aslong as possible, which might even have the length of the greatest dimension of the basis of the mold, the horizontal cross section area of the slots, designed to serve as rising cross section for the casting metal, he-

ing greater than the vertical cross section are creasing the diameter of the commonly used circular vent holes.

By following to invention t e structure of the ingots is favorably influenced and the casting process simplified, the expenses being reduced. Other novel effects, besides the avoidance of the above stated inconveniences, are therefore obtained.

' The invention consists further in the proposal, to fit the casting beds of the usual type with channel stones according to the invention in such a manner, that the cross section sizes of the vent holes of the casting bed supplied from a common charging hopper are different, in consideration of the influences determining the filling speed of every individual mold, that similar rising speeds of the casting metal are obtained in all the molds. It becomes thus possible to simultaneously cast from one casting bed in molds of different cross section sizes, without the danger of irregular rising of the ingots which would otherwise occur.

The channel stones according to the invention may be constructed and arranged in the most different manners. A suitable form of construction of the channel stone is obtained, if the vent hole'formed by the slot is adapted to be closed by a slidable cover plate. In this case new foundry technical working methods are realized, which will be hereinafter described and which also form part of the invention. The slidable covers can be guided in dove-tailor similar grooves of the walls of the longitudinalv slots in the channel stone so that they automatically pack valve-like through casting pressure.

A further object of the invention is, to equip the casting beds with channel stones in such a manner that a surplus number of slot shaped vent holes are in the casting bed, said vent holes being adapted to be shut off singly or in cups. The casting beds thus prepared can be directly used for the most various casting programs, simply by shutting off the vent holes which are not required.

By the invention a quite new process'for filling the molds becomes possible, which consists in using the novel channel stones to regulate from mold to mold the flowing speed of the casting metal designed to fill molds placed the prescriptions according longer. necessar to pour particularly slowly as also the out ow cross-section is larger.

The quality of the casting is further improved in another respect, if channel stones according to the invention are used which have continuous slots, preferably longitudinal slots, it being possible to regulate the position and length of the vent slots to the requirements of the individual caseeven shortly before the casting-within wide limits by means of a slidable element.

However owing to the fact that in this form of application of the new process the channels remain open right to the last, it is possible to see that no foreign bodies or 'no dreaded mortar beards are present on the joints. Thus many an ingot may be saved from going to the waste heap which otherwise would be spoiled by such foreign bodies and flow obstructions.

1 Moreover it is possible, according to the invention, to regulate the rising speed of each ingot in each mould by means of the slidable elements so that in all moulds of the same bed-even for ingots of different sizes-the same conditions are obtained.

As according to the invention the width of the slot is only a fraction of the diameter of the channel, it is possible with the new process in spite of the maximum cross-section of slot to obtain a quick, easy and clean removing of the runner, as it is then attached to the ingot only by a correspondingly thin neck.

The invention relates further to the special arrangement of apparatus for carrying out the new process. 'One of such apparatus according to the invention consists of a casting bed with channel stones having slots, preferably longitudinal, adapted to e shut as desired by longitudinally slidable elements. Contrary to the methods hitherto in use such an apparatus can be made to suit the size and number of moulds to be fed and to the kind of casting without regard to the size and number of moulds to be provided and to the kind of cast, the slidable elements have only to be slid in their grooves at the last minute. This advantage effects a saving in work and time and even permits a changing of casting program at any time in usin the beds which have already been got ready.

A specially favourable form of construction of the new apparatus is obtained if suitably shaped grooves are provided in the walls of the slots for holding and guiding the slidable elements, namely preferably in such a way that these elements are liftedwhen casting pressure occurs and pack them like valves. At the same time it is possible to exert a jet steadying efiect by enlarging the cross-section of the slot and byseeing that the whole shape is suitable for a favourable flow of the jet in the vent slot, another improvement according to the invention greatly facilitates the use 0 sists in making the slidable element in the shape of rods with notches adapted to be broken at a suitable length, so that, besides a universal channel stone, universal longitudinally slidable elements are available for carrying the invention into effect.

Fig. 1 of the accompanying drawing shows a cross-section through a channel stone a built according to the invention with the slide 7) of hexagonal cross-section in suitably shaped grooves in the walls of a slot leading from the channel.

Fig. 2 shows a casting plate made according to the invention with the moulds read for casting, whereas Fig. 3 shows the steady flow of the casting material.

The effect of the new method is obtained also when the slots for casting material are arranged more or less oblique or transversely to the longitudinal axis of the channel stones, provided the total length of the slots in each mould is sufiiciently great.

I claim: I y

1. A refractory channel stone having a slot-like opening in its upper surface and connecting with the channel, and a slidable refractory element located in the opening and adapted to act as a valve for the channel.

2. A refractory channel stone having a slot-like opening in its upper surface the horizontal cross sectional area of which is greater than the vertical cross sectional area of the channel, and a slidable refractory element located in the opening and adapted to act as a valve for the channel. I

3. A refractory channel stone having a slot-like opening in its upper surface and connecting with the channel, and a slidable refractory element having a vertical hexagonal cross sectional area located in the opening and adapted to act as a valve for the channel.

In testimony whereof I ailix my signatur' THEODOR BRINKMANN.

the apparatus. It con- I 

